1To Thomas Jefferson from John Keehmle, 16 March 1805 (Jefferson Papers)
Having read your communication to Congress, in which you noticed the lead Mines in Louisianna, I was induced to make a trial of calcining raw into red lead. Having succeeded in the experiment, I shewed a sample of it, to Tench Cox Esqr. who informed me, that he would forward it to you, with information, that if Congress should think it proper and advantagious to the interest of the United...